Computing machine



Feb. 9, 1932. J. c. HOCHMAN COMPUTING MACHiNE Filed March 6, 1924 4 Sheets Sheet l v Feb. 9, 1932. J, c, HQCHMAN 1,844,470

COMPUTING MACHINE Filed March 6, 1924 4 Sheets-Sheet 2 INVENTOR Lia/{um [MW/man 3 BY @w aw -26" 6 X/MJV j. ATTORNEYS Feb. 9, 1932. J. c. HOCHMAN 1,844,470

COMPUTING MACHINE Filed March 6, 1924 4 Sheets-Sheet 3 jg). Y b Jillian flied/flan @eal,t7aie,if@ a%fq M.

M ATTORNEYS Feb, 9, 1932. J, HOCHMAN 1,844,470

COMPUTING MACHINE Filed March 6, 1924 4 Sheets-Sheet 4 Z I 0 15 93; Z 7 2 l l 7 INVENTOR A BY m- LQWA.

ATTORNEYS r, in

Patented Feb. 9, 1932 UITED STATES ATENT QFFEQE JULIUS C. HOCHMAN, OF NEW YORK, N. Y., ASSIGNOR OF ONE-HALF TO MAURICE SAMBURG, OF NEW YORK, N. Y.

COMPUTING MACHINE Application filed March 6, 1924. Serial No. 637,228.

My present invention relates to computing machines and is concerned in its more specific applications with adding and subtracting machines.

It is among the objects of the invention to provide a machine of the above type of compact and rugged construction, which can be manufactured at low cost, which while including various safeguarding and con trolling appurtenances to assure accuracy in operation, shall yet be compact in proportions and easy to operate manually.

The invention although it may be em bodied in computing machines of various types, has a preferred field of application to key-operated machines generally, and in a specific application relates to adding machines adapted to be attached to typewriting machines for conjoint operation therewith, especially to machines of the type disclosed and claimed in the patents granted to Maurice Samburg and myself jointly, Patent No. 1,609,205 and Patent No. 1,609,206 issued on November th 1930.

According to my invention, the accumulator is driven through a clutch, the driver of which is uniformly and non-selectively operated, the driven element of which is set or closed by a selective action controlled from the operatin keys. In a preferred application, the selective clutch setting or closing mechanism comprises a single clutch shifting member operated in the actuation of each of the number keys, at a corresponding stage in the functioning of the mechanism. The clutch shifting mechanism may include a plate mounted for parallel-motion thereof and having fingers thereon of graduated lengths each to be engaged and shifted by the corresponding operating key. For lightness of operation, the clutch shifting plate is retur ed to normal position alter each operation by t rust transmitted through as sociated parts of the mechanism, rather than by a special. return s a ring.

To minimize the load and wear during the return of the mechanism after operation, and to allow the clutch to open upon completion of the driving stroke, I prefer to provide a special push pawl on the clutch shifting plate, through which the clutch is actuated, said pawl tripped by the operating mechanism at the end of the operating stroke and prior to return of the clutch shifting plate to home position.

The d iving clutch is operated throughout the operative stroke of the machine regardless of the key depressed, and is so related with respect to the driven clutch that effective drive of the latter commences only when the clutch has been completely closed. For this purpose, the coac ting teeth between the driving and the driven clutch are normally displaced with respect to each other rotarily to correspond with the shifting conformations on the clutch shifting plate, so that the shift of the latter is completed the instant the tooth of the clutch driving member has caught up to a tooth of the driven member.

After the driven clutch has been disengaged from the coacting driving clutch member, preferably by the operation of a coil spring. subsequent to the tripping of the push pawl, there is a possibility of overthrow thereof, by inertia which if not obviated. would render the machine inaccurate. A locking pawl coacting with the master wheel toprevent overthrow of the latter might alone not be entirely effective with respect to the dri en clutch member in view of the substantial backlash in the intervening transmission. Accordingly by my present invention, I provide special means acting directly on the driven clutch member to assure accurate positioning thereof at the end of each operation. This means may comprise a protruding tooth on a shaft driven direct from the operating mechanism and, therefore, not subject to bad: lash or overthrow and automatically interposed in the path of a tooth of the driven clutch for the desired purpose.

According to one embodiment, the shaft may be driven at a rate such that the protruding tooth functions as a limiting stop without aiding the rotation of the driven clutch. According to another embodiment, the tooth may be driven at a speed equal to or somewhat greater than the driven clutch, so as to assist the rotation of the latter toward the end of the operation thereof and to then block its further advance.

As a further safeguard preferably in addition to the mechanism referred to, I provide a stationary stop in the path of lateral disengaging shift of the clutch which is of width to be straddled by successive teeth on the driven clutch member. when the latter is properly positioned in idle position, thereby functioning in the event of lag of the driven clutch to block the complete disengagement of the latter, so that the driving clutch would continue carrying the driven clutch around until it is in registry with respect to the aligning stop.

The master wheel locking pawl and other safeguarding mechanisms not in themselves material to the invention claimed herein. may be operated from a control plate, which, in turn. performs an identical operation regardless which of the keys is depressed, the keys having preferably projections that engage said. plate. A lock pl ate is preferably provided which automaticallv interlocks the actuated key with the control plate immediately after the commencement of the operation, to subject the key itself to the safeguardinn; control. said clutch shifting plate being actuated from another part of said same key projection. For accuracy of operation, the accumulator driving gears are preferablv. as is customary, provided each with a multiple of nine teeth. If in such construction. a manuallv set reversing gear in the transmission train to the accumulator, were set in the course of the operative or return stroke of a key, it might obviously mesh at fractional teeth, thereby locking or jamming the machine. By my invention, this is prevented by blocking conformations preferably on the reversing gear. which extend up to the pitch circle between those teeth at which entry into mesh is to be prevented.

In the accompanying drawings in which is shown one of various possible embodiments of the several features of the invention,

Fig. 1 is an elevation with the cover partly removed, showing details of the mechanism,

Fig. 2 is an elevation, with the casing removed indicating the clutch shifting plate and related parts,

Fig. 3 is a perspective view on a greatly enlarged scale of the end of the key bar,

Fig. 4 is a view on an enlarged scale of the construction at the left end of Fig. 1,

Fig. 5 is a transverse sectional view taken on the line 55 of Fig. 4:,

Fig. 6 is a transverse sectional view taken along the'line 6-6 of Fig. 4,

Fig. 7 is a sectional view taken along the line 77 of Fig. 5,

Fig. 8 is a transverse sectional view taken along the line 88 of Fig. 1,

Figs. 9 and 10 are detail views showing alternative means for preventing overthrow of a clutch driven member.

Fig. 11 is a fragmentary detail View indicating the relation of the rack plate and keys, and;

Fig. 12 is an elevation on an enlarged scalc indicating the construction of the escapemcnt rack.

Similar reference characters refer to similar parts throughout the several Views of the drawings.

The present invention in the preferred embodiment shown, constitutes an improvement over the construction shown in the copending applications heretofore mentioned, although the invention has a broader field of application to many other types of computing mechanism. I have shown in the drawings only those features of the subject-matter of the prior applications which are essential to an understanding of a preferred embodiment of the present invention.

This construction includes a back plate 10 which may be mounted in front of the name plate (not shown) of a typewriting machine. A retaining plate (not shown) maintains in position upon the hack plate, a set of key bars 12. each slidable in a corresponding groove 13 extending the height of the back plate. Each key bar has a forwardly extending keybracket 14 rigid therewith. The accumulator a here indicated, is identical with that shown in the copending applications above referred to, and it need, therefore, be simply noted here that said mechanism includes a succession of number wheels 15 mounted in carriage 16, and shiftable manually along shaf 17 for tabulation purposes by a shift lever 18. The shift lever 18 is preferably integral with the carriage and has at its base a curved connection 18 with the carriage, to avoid sharp bends that might weaken the metal and cause the shift lever to break off either in opera tion or in handling The master wheel 19 is mounted upon an operating shaft 20 having bearings in the side walls of the, casing, the cover of which is shown at h. A succession of carrying idlers 21 are mounted on sleeve and transmit to the number wheels through appropriate gears 22. To aid in maintaining alignment of the carrying idlers 21, I provide aligning pawls 23 cooperating therewith and actuated from an aligning drum 24, which derives its motive power from a coaxial coil spring 25, that is energized from aligner shaft 26, extending across the width of the mechanism and driven from the operating shaft 20 through gears 27 and 28. The

details of the aligning mechanism, taken! by themselves are not my invention, and need, therefore, not be set forth in detail, this subject-matter being fully shown and claimed in the copending application of G. O. Degener, Serial No. 585,630 filed September 1st, 1922.

For actuating the operating shaft 20, and for other purposes set forth hereinafter, I provide a control plate 29 extending transversely across the width of the machine and depressed by engagement with the upper edge thereof, of out-turned tongues 30 formed at the upper ends of the key bars. The operat ing shaft and the control plate are returned to home position, after operation by any key, by means of the return spring 0. The control plate has racks 31 integral therewith at its ends meshing with corresponding gears 32 at the ends of the operating shaft'20. T he control plate in the preferred construction, transmits the motive power for of the operations performed by the constituent ele ments of the machine, including not only the driving of the accumulator, but the actuation of the overthrow prevention appurtenances and other safeguarding mechanisms, some of which will be described hereinafter.

As in my copending applications, I prefer in the present embodiment also, to employ a lock plate 33 which will automatically secure any actuated key bar with respect to the control plate 29, near the beginning of its stroke, and maintain it secured with respect thereto, substantially throughout the complete range of its operative and return stroke, so that the full-stroke mechanism (not shown) and any other safeguarding or controlling instrumentalities will control the operation not only of the computing mechanism per se, but of the key also. The preferred construction, for this purpose, includes the plate 33 supported upon the back of the control plate by pins 34 in the latter,

extending into corresponding longitudinal slots 35 in the former. Lock plate 38 has integral hooks 36 at the upper edge thereof, corresponding one to each key, each adapted to straddle the left edge of the out-turned tongue 30 of the corresponding rey bar. The plate 33, moreover, has a roller (not shown) thereon guided by a stationary cam structure 37 mounted on the back plate, so that in the downward movement of a key and with it of the control plate, the roller on the loci: plate will be shifted by the cam 3'7 to the right longitudinally of the control plate, to cause the hoo ing conformation 36 correlg to the actuated key to straddle the i l tongue 30 thereof. The resultant of the downward movement of the lock plate with the control plate and lateral movement relative to the control plate due to the action of cam is an, eh one movement of said lock plate at the beg ning of its stroke, which oblique nio-vemer however, should avoid interlock or other terference with the non-actuated keys. This is brou t about by bevelling as 38 he upper edges of the hooking conformations on the lock plate, and similarly beveling at 89, the corresponding edges of the key bar tongues, so that in the oblique movement of the lock plate, the bevel of each hook will pass by the bevel of the corresponding nonactuated key.

The selective operation of the accumulator according to the number value of the actuated key acted by appropriate control of a driving clutch in the transmission between the control plate 29 and the master wheel 19. This clutch includes a driving clutch member l9 formed an integral hub on the operating shaft .20 an d a driven clutch member 41 coaxial therewith and normally maintained disengaged from the driving clutch by a il 7 nsion spring 4:2 about the aligner shaft 26, which acts through a shifting fork ii-3 mounted on the aligner shaft and straddling a corresponding groove 14.- in the driven clutch 1 ember. The driven clutch member is connected to the master wheel 19 through a composite gear 45 mounted on the accumulator shaft, said composite gear including a gear 4:6 meshing with agear 47 on the driven clutch, and a further gear 4L8 meshing in normal adding position (not shown) with a gear 49 on the end of the sleeve 50, upon which the carrier idlers 21 are car ried, the master wheel 19 being formed integral with the opposite end of the sleeve 50.

The preferred clutch, as shown best in Fig.

it, a dog clutch, which includes a single tooth 51 on the driving hub and nine teeth 52 in the driven clutch member, one corresponding to the number value of each key. The clutch setting means comprises preferably a clutch shifting or selector plate 53 extending transversely across the mechanism and having inegral upstanding .iin ers 54; in the plane 11 "hereof, or graduated length, each to be d1slaced by the corresponding key bar 12. The late mounted for low-friction parallel movement toward the left, under the direct operation of the keys. For this purpose, the clutch shifter plate is preferably suspended air of identical parallel links 55 and 56 pivoted at 57 to the back plate and as at 8 their lower ends near the opposite ends f the clutch shifting plate. To prevent ossible shifting or cocking of the clutch shifting plat-e out of the plane thereof, I provide retaining studs 59 mounted in the back plate l0, and having keris straddling the lower edge of the clutch plate. To assist further to this end, I provide additional studs 60 adjacent links 55 and 56, the heads of which studs overlap the respective links as well as the contiguous fingers 54, there being sufficient clearance with respect to the stems of said studs to permit the lateral displacement of plate 53 required for clutch operation. The fingers, as indicated, are beveled at their upper edges as at 61 in the th of the displacement of the corresponding key bar tongues 30, so that a key bar is depressed, it will after the out-turned tongue 30 thereof comes into engagement with the beveled edge of the corresponding finger shift the latter toward the left, thereby imparting a parallel-link motion to the clutch shifting plate toward the left, so that the latter will close the clutch, the tongue 30 of the operated l in the continued operation, afterit has cle r vhe bevel 61, aassing along the right of the corresponding tongue, so mat the clutch shifting plate operates not only to close the clutch, but to maintain it closed through tie st of the operative stroke.

The clutch shifting plate does not extend to the extreme left of the key, so as to leave the needed space for the parallel shifting movement thereof. l'kccordingly, the extreme key bar, in this case the number 2 bar, as shown, is curved toward the right at its upper end as at 62, to a sufficient extentto effect the operation set forth. To avoid conflict with the stationary lock plate shifting cam 37, the number 7 key is similarly defiemed as shown at 68.

To avoid undue wear or the possibility of jamming, which might be incurred if the sharp edge of thekey bar tongue 30 were to contact the eveled or camming conformation 61 on the clutch shifting plate, it is preferred to bevel as at 64 the edge of the id key bar tongue, so that there will be a surface to surface engagement with respect to the bevel on the tongue of the clutch shifting plate, said bevel, however, not extending through the entire thickness of he key bar ton ue, so that a substantial surface area 65 is left along which the right vertical edge of the tongue 54 slides in key operation.

Means to be described hereinafter serves to accurately position the driven clutch member in its normal inactive position relative to the driving clutch member. As best shown in Fig. 4, the driving face of the driving tooth 51 is normally about the width of two-thirds of a tooth behind the first tooth on the driven clutch member, with which it can coact. It1s preferred, as sh own in the drawings,to provide the lower end of the bevel 61 on the tongues 54 of the clutch sh fting plate at such level that the lateral shift of the clutch setting plate will be completed simultaneously with the abutting of driving tooth 51 against the driven side of a tooth of the driven clutch member, it being remembered that the driving clutch member 40 commences its rotation substantially at the outset of the key stroke. The clutch will, accordingly, always drive on the full width of a tooth and the wear and possible fracture which might result from driving merely at a point of the tooth 1s avoided.

Means is provided for automatically tripping or releasing the clutch 4041 substantially the instant it has completed its accumulator-driving function, so that in the return action of the machine, the driving clutch member will rotate free from engagement with the driven clutch member. For this purpose, I mount on the clutch shifting plate 53 and by a pivot pin 66, a push pawl 67, the tip 68 of which engages the rearward tongue 69 on the pawl shifting fork 43. The pawl has an integral downstruck stop tongue 7 O normally drawn by a coil spring 71 into engagement with the lower edge of the clutch shifting plate. The tip 68 of the pawl provides a vertical edge, preferably substantially at the level of the pawl pivot, so as to provide an effective thrust-transmitting member unlikely to shift about its pivot in the clutch shifting action. The pawl is also provided with a tongue 72 protruding forward therefrom and in the path of operation of the control plate 29, a notch 7 2' in said control plate engaging tongue 72 and raising the tip 68 of push pawl 67 about its pivot at the very end of the control plate stroke, that is, after the clutch has completed the accumulator advancing operation. It will be seen that when the tripping pawl is thus elevated, above the tongue 69, on the clutch shifting yoke, the coil spring 42 will immediately shift the driven clutch member to the right, so that in the subsequent return of the operating parts, the driving clutch member will be free from con tact with the driven clutch member.

Preferably the parallel links 55 and 56 are provided with arms 73 extending to the right from near the upper pivots 57 thereof, said arms having outwardly bent tongues 74 engaged as best shown in Fig. 11 by corresponding integral lugs 7 5 on the control plate and near the end of the return movement of the latter. The parallel links 55 and 56 will thus be simultaneously moved about their pivots toward the right to return the clutch operating plate by a parallel-link motion to the initial position best shown in Fig. 2. In the latter action, as will be apparent, the push pawl 67 will ride from off the tongue 69 on the clutch shifting fork 43 to be drawn by the contraction of spring to the limiting position shown in Figs. 1, 2 and 4, in readiness for the subsequent operation.

To accurately position the master wheel 19 obviating overthrow as well as underthrow thereof, I provide a locking pawl 76 therefor similar to that disclosed in the copending application of G. O. Degener above referred to. said pawl pivoted at 77 in a bracket 77 secured to the frame and having a tongue 7 8 in the range of the lower edge of the control plate 29. Near the end of the operative stroke of the control plate, pawl 76 is shifted thereby int-o coaction with the master wheel, and concurrently a tongue 79 releases hub 24 so that spring 25 in which energy was stored during the operating stroke, drives sleeve 24 to align the carrying idlers for the accumulator.

The pawl 7 6 though effective for locking the master Wheel against overthrow may not be sufiiciently rapid to prevent overthrow of the driven clutch member 41 after the same has passed out of engagement with the driving member, since there may be substantial back lash in the transmission between the master wheel and the clutch member. I have accordingly provided special means coacting directly with the driven clutch member for preventing such overthrow. This means may include a stop member driven directly from the control plate, and, therefore, not subject to inertia overthrow and entering into the path of a gear tooth on the clutch member to block inertia advance. To avoid the possibility of blocking the driven clutch member on a half-tooth, only nine teeth 80 are provided in the range of the blocking member, while the transmission driving gear portion 47 of the clutch would preferably have 18 or some greater multiple of nine teeth for accuracy of operation. The blocking member comprises a tongue 81 protruding from a hub 82 pinned or otherwise secured to the aligner shaft 26 which, as heretofore described, is driven directly Without possibility of overthrow from the control plate. As best shown in Fig. 9, the protrud ing tongue 81 is of width less than the space between consecutive teeth on the clutch member and as the driven clutch member 41 is shifted out of engagement from the driving member to the position shown in Fig. 7, the tooth 81 enters between consecutive teeth 80 of the clutch until at the end of the operating stroke. said tooth occupies a definite position shown in Fig. 9, in which it blocks the further advance of the contiguous tooth 80. In this action, it will be seen that the tooth 81 acts as a stop interposed in the path of rotary movement of the tooth to arrest possible inertia advance of the clutch member beyond said limiting position.

In Fig. 10 is shown a somewhat modified form of the invention in which I provide a lug 83 constructed and arranged generally as in Fig. 9, but of greater width and driven at greater peripheral speed from the aligner shaft 26, as by appropriate change of the driving gearing between the operating and the aligner shafts. In this embodiment, the tooth 83 enters into engagement with a tooth 84 on the clutch gear 41, as shown and assists in driving it toward the end of its disengaging movement, blocking, however, any inertia advance as clearly shown in Fig. 10 by the engagement of the point of the succeeding tooth 84 with the outer edge of lug 83.

In addition, to the overthrow prevention means, I prefer to provide means for preventing possible underthrow of the driven clutch member. This means may comprise a stationary lug 85 riveted as at 86 into the transverse rod 87 that connects the side plates of the machine, said lug having a head 88 at its outer end, tapering as at 89 to a width to be straddled by consecutive teeth of the driven clutch member in the outermost position of the latter, as best shown in Fig. 7. Should the driven clutch member 41 at any time sui'l'er undorthrow, one of the teeth 80 of said clutch would abut during clutch disengagement, against the narrowed point of head 88, blocking complete disengagement. The tooth 51 of the driving clutch 40 would accordingly continue the driving of the driven clutch member through the small angle needed to bring about correct registry of the clutch gear with the head 88, whereupon the expansion of spring 42 would complete disengagement of the clutch, so that the parts would occupy the position shown in Fi 7. The stationary lug 85, not only prevent-s underthrow of the driven clutch, as just described, but is also an instrumentality for aiding in the prevention of overthrow for, after the lug-head 88 is straddled as in 1g. 7, the driven clutch member 41 is locked against overthrow. The lug-head 88 also prevents eventual overthrow of driven clutch member 17 during the progress of a keystroke, as such overthrow could not occur without lateral separation from the driving clutch member, by reason of the incline of the clutch teeth and lug-head 88 prevents such lateral separation. Though either the rotating lugs of Figs. 9 or 10 may be used alone to fix the disengaged position of the clutch or the stationary lug 85 alone may be used for this purpose, it is preferred, as set forth, to use both said instrumentalities in combination for assuring accurate positioning without either lag or lead of the driven clutch at the end of each operation.

In the present embodiment, I have shown a reversing gearing in the accumulator-actuating transmission so that the adding machine thus far described can be used for direct sub,- tract-ion. For this purpose, I provide an extra reversing gear 99 mounted on a stub shaft 49 and permanently in mesh with gear 49 but out of mesh with gears 48, the teeth of the reversing gear normally extending into the space 91 between the narrow gear crowns 48 and 48 on hub 45, and out of mesh therewith. The composite gear 45 is connected by a yoke plate 92 to a shift button 93 telescoped over the end of the shaft 17, the button being in its outermost position for the adding setting. lVhen button 98 is pushed inward, the gear 48 passes out of mesh with gear 49 and the gear 48 into mesh with reversing gear 90, which now constitutes an additional idler in the transmission, so that the accumulator is driven in reverse direction. As heretofore set forth, for accuracy of operation, the various gears 46, 48 and 49 are provided with a multiple of nine rather than only nine teeth, in the present illustrative example, with 18 whole numbers.

teeth, If, an 'impetuous operator should in the course of a key stroke rather than while the machine is in normal non-operated position, shift the button 93 for reverse, the probabilities would be one in two, in the case of the 18 tooth gears, that the machine would thereby become locked against operation. 1 I

1111s would occur if a tooth on gear 48 corresponding to a half number should enter into mesh with the reversing gear 90. In that case, the entire machine would become a half tooth out of phase, causing the master wheel control pawl 76 to strike on top of a tooth of the master wheel rather than between teeth.

5 The control plate then could not complete means to prevent the two coacting gears entering into mesh at half teeth. 1n the preferred embodiment shown, these blocking conformations are formed as integral tabs 9 1 on the left ends of the teeth of the reversing gear 90, said tabs bent at right angles to the length of the tooth alternately in opposite directions. Thus, obstruction pockets or webs 95 are formed joining successive pairs of teeth, while between successive pockets, the

continuity of the passage 96 for entry into mesh with gear 48 remains uninterrupted. Free passage therefor for entry of the gear 18 into mesh with the reversing gear would be presented only between teeth corresponding to the whole numbers and not between teeth correspoding to half numbers. In the preferred embodiment, as shown, the tabs 94- extend approximately up to the level of the pitch circle of the reversing gear. It follows that in pressing inward the reversing button 93 in the course of the operation of a key, the gear 48 would be blocked against entry for mesh with the reversing gear should one of the obstruction pockets 95 be impinged thereby.

Only when a tooth of gear 18 is in substantially precisely accurate alignment with an uninterrupted space between successive teeth of reversing gear can mesh occur. Any small relative displacement from correctly aligned position would cause some part of the obstruction 95 to be located in the path of a tooth of gear 48, thereby preventing mesh. Shift to subtraction can, therefore, take place only with those teeth corresponding to the It follows that the machine is fool-proof and cannot become locked or jammed.

The escapement In Fig. 12 I have shown an improvement on the escapement shown in the copending joint applications above referred to, and shown in a further improved form in my application jointly with G. 0. Deg

ener, Serial No. 516,015 filed November 18, 1921. The escapement mechanism includes a ratchet rack lever 97 pivoted as at 98 to a frame portion 99 on the totalizer carriage. The rack is urged downwardly by a coil spring 100 toward a stationary pawl tooth 101, and a spring (not shown) tends to urge the totalizer toward the left, the movement being normally arrested by the contact of stationary pawl 101 with one of the teeth 102 of the rack. The coil spring 100 is secured at one end to the lever and at the other end to a tongue 103 on the frame piece 9. A lever 1041 has a fixed pivot 105 intermediate its ends, and the end is formed with a lug 106 to be contacted and depressed by the lower edge of the control plate 29 when an operating key reaches the end of its operative stroke, so as to raise the opposite end 107 of the lever to elevate a piece 108 pivoted as at 109 to the frame of the machine and having a tooth 108 formed integral therewith, the ratchet rack lever 97 being, in turn, raised by said tooth 108 on said piece to clear pawl 101 and to permit the spring (not shown) to advance the totalizer through the width of one number wheel and no further. Stationary pawl tooth 110 prevents overthrow of the escapement rack. Frictional load and wear would be engendered if the spring 100 were allowed to draw the tooth into contact with the upper edge of pawl tooth 101. This is avoided by a stop construction 111 against which the spring 100 urges lever 97, and to maintain a slight clearance, as shown in the drawings, with respect to the pawl 101 which is engaged only by the operative face of the ratchet tooth. For accuracy of settting of the ratchet rack plate and to compensate for wear, the stop 111 is, in the form of an eccentric, as shown, and may be readily adjusted in accordance with requirements, to avoid dragging of the lower edge of plate 97 over pawl 101 in escapement operation.

The operation which has been set forth fully in the foregoing description will now be briefly summarized. After the accumulator has been placed in tabulated position by shifting of finger piece 18, the number keys are operated. Upon depression of any number key, the tongue thereof near the be ginning of the stroke depresses the control plate 29 and with it the lock plate 33 carried thereby. By the cam conformation 37, the lock plate is shifted near the beginning of the stroke, so that the notch of tongue 38 thereof is straddled laterally over key tongue 30 to lock the same relative to the control plate. The beveled ends of the hooks 38 on the lock plate corresponding to the other keys, readily clear the corresponding beveled edges 39 of the other key tongues 30, so that only the selected or depressed kev is locked with respect to the tongue and the remaining keys remain free. The various safeguarding means, therefore, control the movement not only of the mechanism, but also of the operating key. As the key-stroke progresses, the beveled edge 64 of the key tongue contacts the beveled end 61 of the corresponding tongue 5 1, so that in the continued depression of the key, the clutch shifting plate 53 is shifted toward the left, transmitting thrust through the push pawl 67 against the yoke 43 to close the clutch el041.

Driving clutch member 40 is rotated from the outset of the stroke, since it is driven through the gear connection 31-32 with the control plate. The shifting described, of the driven clutch 41 is completed the instant the driving tooth 51 of clutch member 40 has caught up with a eoacting tooth face on the driven clutch member 41. Thus, at the phase of the key stroke corresponding to the number value thereof, the accumulator driving clutch is closed and thereafter throughout the rest of the operative stroke, is maintained closed by the engagement of surface 65 of the operating key tongue with the vertical edge of the coacting tongue on the clutch shifting plate. In the rest of the operation, the clutch operates through the driven clutch member and the composite gear 45 to drive the gear 419 through which the master wheel 19 is o erated to actuate the accumulator in the well known manner.

Substantially at the end of the operative stroke, the lower edge of the control plate engages and then depresses the tail 7 8 on the pawl 76, to cause the tooth thereof to enter between teeth of the master wheel to block the same against overthrow. The control plate also substantially at the end of its operative stroke engages the upstanding tooth '4' 2 on the pawl 67, tripping the latter so that the spring 42 of the clutch, shifts the latter open position, the tongue 69 on the clutch shifting yoke, riding under the trip pa l 6'7.

The driven clutch member 11 substantially at the same instant is blocked against overthrow by the operation heretofore set forth at length, of the positively driven hub 82 and lug 81 on the aligner shaft 26, or by the alternative construction shown in Fig. 10. The stationary lug 87', moreover, by the action of its beveled head, serves to correctly position the driven clutch member, it being understood, that in the event of a tooth on the driven clutch member entering into the path of the head 88, complete disengagement of the clutch is prevented until the driving clutch member has dragged the driven clutch member through the small angle needed to effect the alignment for straddling said head 88 in the manner best shown in i". More over, at the end of the operative stroke of the control plate, the latter engages the end of lever bar 10%, shifting the same about its pivot 105 to elevate the pawl 108 and its tooth 108' to raise the ratchet rack lever 97, so that the accumulator can be automatically drawn to the left throu h the width of one number wheel. in the return stroke of the key under the lifting effort of the return spring G, the key tongue rides along the vertical edge of the corresponding linger 5% on the clutch shifting plate until near the end of the return stroke, the upper edge of the control plate strikes the ledge 7 on the lateral arms of the parallel supporting links 56 shifting the latter in a counterclockwise direction to return the clutch control plate to the home position shown in Fig. 2, during which return the lower edge of the trip pawl 67 rides from off the tongue 69 on the clutch shifting yoke, the spring 70 thereupon returning the pawl to the position best shown in Figs. 1 and 2 in readiness for the next operation.

Other features of the operation are so fully set forth in connection with the descrip tion of the construction thereof in the foregoing, that a detailed recital here would involve substantially mere repetition and is, accordingly, d'spensed with.

Alternate 0e tote/Z6267 In Figs. 13 to 16 l have shown an alternative form of totalizer of eneral application, which may be used in the construction of Figs. 1 to 12 in lieu of that there shown. It maybe noted that in a familiar form of totalizer of the type shown, for instance, in the patent to lVolfl e, No. 578,303, dated March 2, 1897, the master wheel drives through a transmission idler which, in turn, meshes with gear teeth on the corresponding number wheel and a set of carrying idlers coaxial with the master wheel mesh each with a pair of consecutive transmission idlers. The carrying operation from any number wheel to the number wheel of next higher order thus takes place through a train of four gears that is, from the single carrying tooth on the actuated number wheel to toe associated transmission idler gear to the carrying idler meshing therewith, to the transmission idler of next higher denomination with which the carrying idler also meshes, to the number wheel of next higher denomination. Under the most unfavorable conditions, that is, where the carrying operation extends through the entire train of the totalizer, for instance, in adding to 999,999, it will be seen that the carrying transmission for a seven place totalizer would thus include 28 gears in series. Vith only the minute back lash at each. gear. desirable for facility of manufacture and lightness of operation, there is thus a possibility of a loss under the most unfavorable conditions noted, of more than half a tooth in which case, of course, the totalizer would introduce an error of one.

rying train so t number of decimal places on the accumulator,

It is among the objects of the invention to prevent the possibility of error due to back lash in the carrying gearing without, however, adding to the complexity of the con struction or to the operating load.

Another object is to simplify the construction of the accumulator and particularly to greatly reduce th number of gears in the carhat even with an increased the back lash shall not be excessive and the operating load shall be reduced.

In the accompanying drawings:

Fig. 13 is a plan of the alternative form of accumulator,

Fig. 1 1 is a front elevation thereof,

Fig. 15 is a transverse sectional view taken along the line 1515 of Fig. 14, and;

Fig. 16 is a perspective view on an enlarged scale of one of the transmission interrupting pawls.

Referring now to the drawings, I have shown a master wheel 115 mounted on an operating shaft 116 and arranged for mesh with any one of a set of idler gears 11? mounted on a corresponding shaft 118. Each idler gear meshes with a corresponding gear crown 119 on an associated number wheel, the group of number wheels being mounted on a shaft 120. The set of idler gears and the set of number wheels are both mounted in a stamped metal carriage 121 shown in this case with the integral lip-struck linger piece 122 by which tabulation is effected and a spring 123 tends to urge said carriage toward tl e left controlled for step by step motion by an escapement action similar to that shown in Fig. 12. The number wheels are of conventional construction, each including in order from the right to the left thereof,

the gear crown 119 already referred to, the number wheel band 124;, t ie Geneva loclrin disk 125 with its notch 126 and the gear 127 having a single tooth 123 aligned with the notch 126. The idler gears are also substantially of conventional construction, each in cluding the gear 117 heretofore referred to, meshing with the gear crown 119 and extending beyond the limiting plane thereof for mesh in carrying with the single tooth 128 of the number wheel of next lower denomination. Each of the idler gears also includes the Geneva star wheel 129 substantially in the plane of the corresponding looking disk 125 of the number wheel of next lower denomination.

The operation of the construction as thus far described will be readily understood. After tabulation, the master wheel would mesh with the corresponding selected idler gear 117 and in operation would drive the same, to advance the associated number wheel. In carrying, the single gear tooth 128 of the driven number wheel would enter into mesh with the idler gear 117 corresponding to the number wheel of next higher denomination, and would drive the latter through the width of one tooth, said range of drive being accurately determined by the Geneva stop motion 126-129 in the well-understood manner. Of course, the construction just described, may also be reversed by adding an extra idler gear into the transmission train to the accumulator in the same manner as shown in Figs. 1 and 4;, said reversing action being useful for subtraction. If the transmitting idler at any instant in mesh with the master wheel should happen to mesh with the single tooth of the number wheel immediately to the right thereof, said idler gear would in operation turn said number wheel through the width of one tooth, thereby introducing an error. If other nu1nber wheels to the right of said latter number wheel were similarly aligned, the peculiar reverse carrying action set forth, would introduce similar errors at other number wheels.

To obviate such erroneous operation, I provide means for automatically interrupting the effectiveness of the transmission train between the idler gear in mesh with the master wheel and the number wheels to the right thereof. In a preferred construction for this purpose, the carriage 121 is of somewhat greater width than the combined widths of the gear and number wheel batch, to afford the necessary length for a gap 130 between the number wheel in active position and the set of number wheels to the right thereof, whereby, as will be seen, the operated idler gear 117 will be ole-meshed with respect to the single tooth of the number wheel of next lower denomination.

A preferred specific construction for the purpose comprises a plate 131 fixed to the casing of the machine and extending above the totalizer carriage and having a cam slot, which has an operative deflection or slope 133 acting substantially at the plane of the master wheel and a restoring or return deflection 12L to the left thereof, merging with a straight slot 134 therebeyond. A succession of separator pawls 135 are mounted on pivots 137 in the cross-plate 136 of the accumulator carriage, said pawls corresponding one to each number wheel. The pawls have each an upstanding linger 138, said fingers adapted to enter successively into the stationary cam slot as the carriage sl ifts during escapement, as will be described hereinafter, each of said fingers having a stop shoulder 139 riding under he cam plate. Each pawl also has an arm 140 extending forward and with a downward lug l ll adapted to engage the number wheel to the right thereof, and of length and width such as to clear the gear 119 and to engage the Geneva locking disk 125 substantially at the rim thereof. The parts are so related that lug 141 will engage the face of Inn said disk 125 regar-dlessfin which of the ten possible noted positions, the locking disk may be,the lug 141always extending at least in part laterally beyond the notch 126, so that it must alway push against the left face of the Geneva locking disk. ,Each pawl, moreover, has an arm 142 extending rearward and provided. with a downwardly turned finger 143 adapted to engage the Geneva starwheel 129 of the number wheel to the left thereof. As shown in the drawings, the widths of the successive separator pawls are such that they mutually position each other in normal or idle position.

In operation after each key actuation, the escapement shifts the. carriage through the width of one number wheel to the left. During escapement, the finger 138 on the pawl immediately to the right of the number wheel, entering into units position engages and rides along the deflection 133 of the cam plate and is thereby turned in a counterclockwise direction about its pivot v137 to the position shown at 135 in Fig. 13, whereby the lug 141 thereof engages the rim of the Geneva locking disk 125 on the number wheel 124* immediately to the right of that entering units position and blocks said number wheel together with those further to the right thereof against advance toward the left, thereby establishing a gap 130. At the same time, the finger 143 on the pawl 135 exerts a positive thrust, correspondingly pushing to the left the idler gear 117 and through the tooth 117 of the latter,'said pawl shifts the number Wheel 124 entering to units or driven position into face to face engagement with the number wheel. 124" of next higher denomination, to close up the gap previously existing between said number wheel 124 and the said number Wheel 124 of next higher denomination. At each step of the escapement thus, the carriage as a whole moves through the width of a number wheel, while the number wheel entering to units position, moves through a greater width, to close up gap 130 with'respect to the number wheel of next higher order, and to establish a similar gap with respect to the number wheel ,of next lower order. f

Briefly, in the course of each step of the escapement, a separate pawl becomes operative to establish a gap for interrupting a possible carrying train from the number wheel entering to units position to that of next lower denomination and at the same time said pawlclos'es the gap which previously eXisted immediately in advance of the number wheel moved to units position, to establish the carrying train therefrom to the number wheels tot-he left thereof. The return deflection 132 of the cam slot, it will be seen shifts the separator pawl135 which has previously acted, back to neutral position, so that it will not interfere with the action of pawl 135 just described. Thus in operation, it will be seen that there is no possibility of carrying backward from the number wheel at any instant in operating or units position to those at the right thereof.

The braking of the carrying or transmission train at the part immediately to the right of the number wheel in driven or units position and the establishment of the train from each number wheel to those of higher denomination, as it enters into driven position, does not add to the operating load of the machine, since the energy for the operation is derived from the spring 123, that actuates the escapement, said spring being energized, of course, in the tabulating operation prior to setting up the number.

It will be understood, or course, that the accumulator described is not limited in its application to a construction of the general type shown in Figs. 1 to 12, but has a preferred field of application to key-operated adding and computing machines generally. The economies effected in bulk and expense, however, render the accumulator shown, of utility in computing machines generally, whether key-operated or key-set, whether manually or power driven. It will also be understood that although I have shown an embodiment of accumulator tabulated by a separate manual operation, the principle of the accumulator is not limited in its application to machines of this type, but can be applied to accumulators of general application, regardless of whether the tabulation is effected or controlled by manual selection or otherwise or by the inherent operation of a key-set machine.

To maintain the idler gear teeth properly aligned to facilitate entry into and out of mesh with respect to the master wheel in the tabulating or escapement operation, I provide a "'Xed rod R extending between teeth of the idler from the right end of the accumulator substantially to the plane of the master wheel 115. To maintain the number wheels against overthrow or any other ad vance from set position, while assuring the readiness of shift in the escapement action, without interfering with carrying-over, I preferably provide a pawl 144 pivoted upon shaft 116 and having an elongated tooth 145 extending from the extreme left position of the left end of the accumulator carriage to substantially the master wheel and having tails 146 at the ends thereof urged by coil springs 147 affixed to bar 148 to maintain the elongated pawl tooth 145 interposed between teeth of all of the idler gears to the left of the master wheel. The pawl tooth 145 has anextension tip 149 at the right end thereof projecting somewhat beyond the left limiting plane of the master wheel, so that, as will be readily seen, in the escapement action, before the idler gear 117 has been shifted completely to the left of the master wheel, tip 149 of the pawl will have entered between teeth of said idler gear so that the latter is correctly positioned. The pawl 144 and the springs 147 thereof are of such strength that the pawl will readily yield in the normal carrying operation through one or through all of the idler gears, whereupon the pawl will be snapped back by springs 147 between teeth of the idler gears. r

I claim 1. In a computing machine, in combination, a bank of number keys, an accumulator, a member for transmitting mechanical force from said keys for actuating the accumulator and a selective cam member actuated by the keys for establishing a mechanical connection between the transmitting member and the accumulator for the interval corresponding to the number value of the actuated key.

2. In a computing machine, in combination, a bank of operating keys, an accumulator, a transmission to said accumulator including a clutch having a horizontal axis, means normally maintaining said clutch in open position, operating keys moving in vertical planes, and a clutch shifting member extending transversely across said keys and having integral upstanding arms of graduated lengths in the path of operation of the corresponding keys, said arms having cam conformations at their upper ends, whereby in the actuation of the keys, the clutch shifting plate will be moved laterally after the key reaches the camming conformation of the plate and in the continued operation of .the key, the latter will maintain the plate against return to clutch opening position during the operative stroke of the machine, and means sustaining and guiding said plate in operation.

3. In an adding machine, in combination, an accumulator, an operating transmission therefor including a clutch having a horizontal axis, said clutch havinga driving member rotatable through an identical range at each adding operation, a driven clutch member, means normally maintaining the clutch in open position, a bank of operating keys, a clutch shifting plate extending transversely across said bank of keys, means sustaining said plate for parallel motion thereof for clutch closure, said plate including a plurality of upstanding fingers of graduated lengths, each finger beveled at its upper end in the range of operation of the corresponding key, for shifting the plate laterally at a definite characteristic portion of each key stroke for closing the clutch at the proper phase of the operation for correct accumulator actuation. V

4. The combination set forth in claim 3 in which the clutch shifting plate is mounted by links for parallel-link movement thereof and in which low-friction means is provided to retain the plate against shifting out of the plane thereof. V r

5. In a computing machine, in combination, a bank of keys having slidable key bars movable therewith, a control plate extending transversely of the machine and in the path of operation of all of said key bars to move through identical range regardless which key is actuated, an accumulator, a transmission therefor including a driving clutch member operated from said control plate, a driven clutch member, means normally maintaining said clutch disengaged and a clutch shifting member extending transversely across the width of the machine, having upstanding fingers of graduated lengths and beveled near their upper edges in the path of operation of the corresponding key bars, whereby in the operation of any key the clutch plate will be shifted laterally to close the clutch at a corresponding stage in the operation, and whereby by reason of the coaction of the key stem with the side of the stem below the bevel, the clutch shifting plate will be maintained in clutch closing position throughout the operation of the accumulator.

6. The combination set forth in claim 5 in which the clutch shifting plate is supported by a pair of parallel links for parallel link movement thereof and in which said links have lateral oifsets in the path of return movement of the control plate for return of the clutch shifting plate to normal position at the end of the return stroke of the control plate.

7. In a computing machine, in combination, a support plate, a clutch shifting plate extending transversely thereacross, parallel link members pivoted on said support plate and sustaining said clutch shifting plate for parallel movement thereof, said plate havin upstanding fingers in the plane thereof and o graduated lengths, and studs mounted in said support plate and coacting with different parts of the edges of said clutch shifting plate and constituting low-friction means maintaining the plate against shifting out of the plane thereof.

8. In a computing machine, in combination, a bank of operating keys, an accumulator, control mechanism operating through identical rangefor each of said keys, mechanism actuated from said keys and having selective operation depending on the number value of the actuated key, said mechanism including a clutch driven from the control mechanism and closed from the selective .mechanism, said selective mechanism including a clutch shifting plate extending transversely across the range of the keys and actuated by the operation of the keys and having a part actuated by the return of the control mechanism for return of said clutch shifting plate from operating position.

for r :9. Inacom utingmechanism, in combination, a bank of slidable keys, an accumulator, a control plate actuated through identical rangebyeach of said keys, a clutch driving membergeared to said control plate, a clutch driven member, spring means for normally maintaining the clutch in open position, a transmission between said clutch driven member and said accumulator, and selective clutch closing means comprising a clutch shifting. plate extending transversely across the variouskey bars and having upstanding fingers of graduate-d lengths, parallel links supporting said clutch shifting plate for parallel motion thereof under the influence ofany one of saidkeys to close the clutch at acorresponding periodcin the operation of the mechanism, said supporting links having lateral offsets actuated by the return of the control plate for shifting the clutch operating plate to ineffective position after completion of the operation.

10. In a computing machine, in combination, a bank of operating keys, an accumulator,[a transmission for operating said accumulator, said transmission including a normally open toothed clutch, means under the influence of'each of the keys to close said clutch and to maintain it closed during the operation of the accumulator, and tripping means operated after completion of the accumulator action to open the clutch near the beginning of the return stroke of the mechanism.

11. In a computing machine, in combination, a bank of operating keys, an accumulator, a transmission for operating the latter and including a normally open clutch, a clutch closing member extending transversely of said keys, and mounted for parallel motion thereof in a clutch closing direction by the actuation of any key, a pawl mounted on said clutch closing plate for transmitting the clutch closing thrust, means for tripping said pawl at the end of the operative stroke to release the clutch, and means for subsequently returning the clutch actuating plate to its initial position.

12. In a mechanism of the character described, in combination, operating keys, an

accumulator, an operating mechanism therefor including a normally open clutch, a clutch closing member under the control of all of said keys for selective operation, said clutch closing member including a pivoted push pawl, and means operating after the completion of the totalizer action to move said pawl about its pivot to permit subsequent release of the clutch.

13. In a computing machine, in combination, a bank of operating keys, an accumu lator, an operating transmission therefor including a clutch having a driving member operated in identical manner for each key, a driven clutch member normally disengaged from said driving member,a shifting fork carried by said driven member, a clutch shifting plate extending transversely across the keys and having selective conformations in the path of operation of each key, and a push pawl pivoted on said clutch shifting plate for coaction with said shifting fork to close the clutch. c

.14. The combination set forth inclaim 13 in which the mechanism includes acontrol element for shifting the pawl about its pivot at the end of the operating strokepreparatory to release of the clutch.

15. In apparatus of the character described, in combination, operating keys, a transmission actuating clutch, acoil spring normally maintaining said clutch in open position, shifting means in the path of actuation of all of said operating keys for closing said clutch, said meansincluding a plate, said plate arranged for parallel lateral motion thereof with the actuation'of the keys, and a push pawl pivoted to said plate for coaction with the clutch, said push pawl having an integral stop tongue, and a spring normally urging said stop tongue against an edge of said plate, and a. second integral tongue projecting out of the plane of said pawl to be engaged by another part of the mechanism for disengagingthe pawl with respect to .the clutch after the latter has completed its operative function.

16. In a computing machine, in combination, a bank of slidable key bars havingprojections, a clutch shift plate extending across said key bars and mounted forparallel motion and having a plurality of upstanding fingers of graduated length in the path of the respective projections of the key bars, said fingers being beveled at their ends and said projections having corresponding bevels for effective engagement of the projection of eachkey in the downward movement thereof with the corresponding finger of the clutch shifting plate to shift the same.

17. As an article of manufacture, a key bar for a computing machine, said barhaving an outturned tongue, provided with a beveled conformation at one edge extending for the thickness of the metal of the tongue'and a contiguous bevel extending through only part of the thickness of-the tongue.

18. In a computing machine, in combination, an operating mechanism, an accumulator, a transmission for operating said ac cumulator including a driving clutch memher, a driven clutch member, a master wheel, gear mechanism interposed between said clutch and said master wheel, means to automatically prevent overthrow of said master wheel at the end of the operative stroke, means to disengage the driven clutch from the driving clutch at the end of the operative stroke, and means to prevent overthrow of said driven clutch member at disengagement,

said means comprising a shaft driven from the operating mechanism and restrained thereby against overthrow, said shaft having a tooth engaging the toothed gear of the driven clutch member and moving at a greater peripheral speed than said gear to aid in carrying the same around at the final portion of its stroke and to block the further advance of therdriven clutch member at the end of the operation.

19. In a computing mechanism, in combination, an accumulator, transmission gearing to said accumulator for one operation, an extra gear for reversing the operation of the mechanism, manual means for placing said extra gear into operation at Will, and blocking means to prevent operation of said reversing mechanism when the parts are so positioned that the connection of the extra gear would tend to block or lock the machine.

20. In a computing machine, in combination, an accumulator, a transmission for operating the same, said transmission including a gear having teeth in number a multiple of the number of operatively set positions thereof, a reversing gear manually displaceable into meshwith said gear for reversing the operation of the computing mechanism, and blocking means rigid with one of said gears to prevent shifting the reversing gear into mesh at a stage of the operation where such shifting would tend to lock the mechanism.

21. In an adding and subtracting machine, in combination, an accumulator, a transmission including a gear having a multiple of nine teeth, an auxiliary reversing gear manually shiftable to mesh with said gear for reversing the operation, said reversing gear having integral blocking conformations to block entry with respect to the transmission gear at teeth at which locking of the-machine would occur. 7 I

22. The combination set forth in claim 21 in which the blocking means comprises pockets between adjoining ends of contiguous teeth and extending approximately to the pitch circle of the reversing gear. g

23. An escapement for a computing machine comprising an escapement ratchet rack lever, a stop pawl coacting therewith and a back stop maintaining the length of said lever free from the edge of the stop pawl for reducing friction. V

24. In a computing machine, in combination, operating keys movable in vertical planes, an accumulator, transmission means for actuating said accumulator, said transmission means including a clutch having a horizontal axis and including a driving member operated by work performed on a key and through identical range for the actuation of each key, and a driven member normally laterally displaced from said driving member and disengaged therefrom, and a clutch shifting memberin the path of operation of said keys and movable thereby at an angle with respect to the stroke of said keys, said clutch shifting member having conformations coacting with the different keys to effect closing of the clutch at a selective stage in the operation corresponding to the numeral value of the operated key by a camming action between said operating keys and said clutch shifting member.

25. In a computing machine, in combination, a bank of operating keys, an accumulator, an operating transmission to said accumulator, including a normally open clutch, a clutch shifting plate extending transversely across all of said keys and having integral conformations of graduated length in the range of the various keys for direct actuation of the shifting plate to positively close the clutch selectively at the stage of the operation corresponding to the number value of the actuated ke said actuated key retaining the clutch shi ter against return from clutch closing relation throughout the interval of accumulator operation.

Signed atNew York, in the county of New York, and State of New York, this 4th day of March, A. D. 1924.

JULIUS C. HOCHMAN. 

